Turns out there is a significant bug in a Windows driver that seriously impacts most attempts at digital communications using a computer.
From Reddit:
Huge Windows bug ruining your receive performance on all digital modes, fix discovered
Edited this for brevity and clarity (tried to, anyway). There's a bug with the USB audio chipset used in many ham radio sound interfaces that occurs in windows vista and later. The affected chipset is the TI PCM2900 series PCM2904 and below, pre-C revisions.
A non-exhaustive list of devices using this chip and therefore have the bug guaranteed:
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- All Icoms with built in USB Audio
- All Kenwoods with built in USB Audio
- All Yaesus with built in USB Audio, as well as the SCU-17 Interface
- All Signalink USB's
If you have one of these devices, and are on windows vista or later, your performance is reduced due to this bug even if you think it's working fine. Wait until you see your performance afterwords :) This is confirmed by Texas Instruments, who never recommended this chipset for use on windows Vista and later in the first place, and also tested with more than 15 50 hams who gained massive receive performance after the fix.
The bug is very odd and has some quirks that bring it back very often even after the fix so I made a detailed video linked below demonstrating the bug, the fix, and showing real measurements of the affected audio on a scope and several meters, and also demonstrating how to properly level your audio in the analog domain and in windows for maximum dynamic range and minimal noise after you fix the bug.
Much more at the site including a 20 minute video demonstrating the problem and showing you the fix. Of course, the "old" part is considered obsolete so don't hold your breath waiting for a patched driver and it is not pin compatible with the new part so no manufacturer is going to offer a hardware fix.
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